Ante-Nicene Fathers, Vol II:
THEOPHILUS: Chapter XXV.—God Was Justified in Forbidding Man to Eat of the Tree of Knowledge.

Chapter XXV.—God Was Justified in Forbidding Man to Eat of the Tree of Knowledge.

The tree of knowledge itself was good, and its fruit was good. For it was not the tree, as some think, but the disobedience, which had death in it. For there was nothing else in the fruit than only knowledge; but knowledge is good when one uses it discreetly. 601
But Adam, being yet an infant in age, was on this account as yet unable to receive knowledge worthily. For now, also, when a child is born it is not at once able to eat bread, but is nourished first with milk, and then, with the increment of years, it advances to solid food. Thus, too, would it have been with Adam; for not as one who grudged him, as some suppose, did God command him not to eat of knowledge. But He wished also to make proof of him, whether he was submissive to His commandment. And at the same time He wished man, infant as he was, 602
to remain for some time longer simple and sincere. For this is holy, not only with God, but also with men, that in simplicity and guilelessness subjection be yielded to parents. But if it is right that children be subject to parents, how much more to the God and Father of all things? Besides, it is unseemly that children in infancy be wise beyond their years; for as in stature one increases in an orderly progress, so also in wisdom. But as when a law has commanded abstinence from anything, and some one has not obeyed, it is obviously not the law which causes punishment, but the disobedience and transgression;—for a father sometimes enjoins on his own child abstinence from certain things, and when he does not obey the paternal order, he is flogged and punished on account of the disobedience; and in this case the actions themselves are not the [cause of] stripes, but the disobedience procures punishment for him who disobeys;—so also for the first man, disobedience procured his expulsion from Paradise. Not, therefore, as if there were any evil in the tree of knowledge; but from his disobedience did man draw, as from a fountain, labour, pain, grief, and at last fall a prey to death.